MONITORING OF RADIOACTIVITY AT DNURT CAMPUS

L. F. Dolina, V. P. Kilovyi, D. V. Astakhov, M. V. Kalimbet

Abstract

Purpose. The research paper aims to determine radioactive contamination on the territory of campus of Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan (DNURT). Methodology. The dosimeters measured the radioactive contamination in different places (points) of DNURT campus, focusing on public places. The centres of measurements became dormitories, monuments, stops, main entrances of the new and the old buildings, classrooms, basements, a swimming pool, boiler room and others. Findings. The conducted radiation monitoring for the first time in the history of the University discovered the source of radioactive contamination on DNURT territory and campus. The highest radiation background is observed on three points, namely: the pedestal of the monument, the monument to students-soldiers, the main entrance of the new building (columns). This can be explained by granite materials, which the pedestals and the stairs are made of. Originality. The largest contribution to the total value of annual effective dose of human exposure is made by ionizing radiation sources (IRS) of building materials (65 - 70%). The radioactivity level of building materials is determined by the content of natural radionuclides that are included in uranium-radium and thorium decay series (18 and 12 radionuclides) as well as potassium-40. Radioactivity of building materials is evaluated by the content of dominant radionuclides radium-226, thorium-232 and potassium-40. Their dominant role is explained by the fact that these long-lived high-energy - emitters are the products of decay of radium-226 in uranium series of and radium-224 in thorium series, exposing radioactive gases (radon-222 and radon-220). Radioactive gases are accumulated in the basements of educational buildings; their decay is accompanied by 100% alpha radiation, which is the most dangerous. Practical value. It is necessary to set radioactivity signs near the objects with high radiation and to prohibit students with children walking there. In order to reduce radon radiation exposure to students and staff the university should be equipped with more effective ventilation of educational building basements, swimming pool and dormitories.

Keywords

radioactive irradiation; monitoring of the university campus; building materials; radon